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            <div><h4 class="title">
                <a name="asio.reference.dispatch.overload2"></a><a class="link" href="overload2.html"
                                                                   title="dispatch (2 of 3 overloads)">dispatch (2 of 3
                overloads)</a>
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    <p>
        Submits a completion token or function object for execution.
    </p>
    <pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
    <span class="keyword">typename</span> <a class="link" href="../Executor1.html" title="Executor requirements">Executor</a><span
                class="special">,</span>
    <span class="keyword">typename</span> <a class="link" href="../NullaryToken.html"
                                             title="Nullary token requirements">NullaryToken</a> <span
                class="special">=</span> <a class="link"
                                            href="../asynchronous_operations.html#asio.reference.asynchronous_operations.default_completion_tokens"><span
                class="emphasis"><em>DEFAULT</em></span></a><span class="special">&gt;</span>
<a class="link"
   href="../asynchronous_operations.html#asio.reference.asynchronous_operations.automatic_deduction_of_initiating_function_return_type"><span
        class="emphasis"><em>DEDUCED</em></span></a> <span class="identifier">dispatch</span><span
                class="special">(</span>
    <span class="keyword">const</span> <span class="identifier">Executor</span> <span class="special">&amp;</span> <span
                class="identifier">ex</span><span class="special">,</span>
    <span class="identifier">NullaryToken</span> <span class="special">&amp;&amp;</span> <span
                class="identifier">token</span> <span class="special">=</span> <a class="link"
                                                                                  href="../asynchronous_operations.html#asio.reference.asynchronous_operations.default_completion_tokens"><span
                class="emphasis"><em>DEFAULT</em></span></a><span class="special">,</span>
    <span class="keyword">typename</span> <span class="identifier">constraint</span><span
                class="special">&lt;</span> <span class="identifier">execution</span><span
                class="special">::</span><span class="identifier">is_executor</span><span
                class="special">&lt;</span> <span class="identifier">Executor</span> <span class="special">&gt;::</span><span
                class="identifier">value</span><span class="special">||</span><span
                class="identifier">is_executor</span><span class="special">&lt;</span> <span
                class="identifier">Executor</span> <span class="special">&gt;::</span><span
                class="identifier">value</span> <span class="special">&gt;::</span><span class="identifier">type</span>  <span
                class="special">=</span> <span class="number">0</span><span class="special">);</span>
</pre>
    <p>
        This function submits an object for execution using the specified executor.
        The function object may be called from the current thread prior to returning
        from <code class="computeroutput"><span class="identifier">dispatch</span><span class="special">()</span></code>.
        Otherwise, it is queued for execution.
    </p>
    <h6>
        <a name="asio.reference.dispatch.overload2.h0"></a>
        <span><a name="asio.reference.dispatch.overload2.parameters"></a></span><a class="link"
                                                                                   href="overload2.html#asio.reference.dispatch.overload2.parameters">Parameters</a>
    </h6>
    <div class="variablelist">
        <p class="title"><b></b></p>
        <dl>
            <dt><span class="term">ex</span></dt>
            <dd><p>
                The target executor.
            </p></dd>
            <dt><span class="term">token</span></dt>
            <dd>
                <p>
                    The <a class="link" href="../../overview/model/completion_tokens.html" title="Completion Tokens">completion
                    token</a> that will be used to produce a completion handler. The
                    function signature of the completion handler must be:
                </p>
                <pre class="programlisting"><span class="keyword">void</span> <span
                        class="identifier">handler</span><span class="special">();</span>
</pre>
            </dd>
        </dl>
    </div>
    <h6>
        <a name="asio.reference.dispatch.overload2.h1"></a>
        <span><a name="asio.reference.dispatch.overload2.return_value"></a></span><a class="link"
                                                                                     href="overload2.html#asio.reference.dispatch.overload2.return_value">Return
        Value</a>
    </h6>
    <p>
        This function returns <code class="computeroutput"><span class="identifier">async_initiate</span><span
            class="special">&lt;</span><span class="identifier">NullaryToken</span><span class="special">,</span> <span
            class="keyword">void</span><span class="special">()&gt;(</span><span class="identifier">Init</span><span
            class="special">{</span><span class="identifier">ex</span><span class="special">},</span> <span
            class="identifier">token</span><span class="special">)</span></code>,
        where <code class="computeroutput"><span class="identifier">Init</span></code> is a function
        object type defined as:
    </p>
    <pre class="programlisting"><span class="keyword">class</span> <span class="identifier">Init</span>
<span class="special">{</span>
<span class="keyword">public</span><span class="special">:</span>
  <span class="keyword">using</span> <span class="identifier">executor_type</span> <span class="special">=</span> <span
                class="identifier">Executor</span><span class="special">;</span>
  <span class="keyword">explicit</span> <span class="identifier">Init</span><span class="special">(</span><span
                class="keyword">const</span> <span class="identifier">Executor</span><span class="special">&amp;</span> <span
                class="identifier">ex</span><span class="special">)</span> <span class="special">:</span> <span
                class="identifier">ex_</span><span class="special">(</span><span class="identifier">ex</span><span
                class="special">)</span> <span class="special">{}</span>
  <span class="identifier">executor_type</span> <span class="identifier">get_executor</span><span
                class="special">()</span> <span class="keyword">const</span> <span class="keyword">noexcept</span> <span
                class="special">{</span> <span class="keyword">return</span> <span class="identifier">ex_</span><span
                class="special">;</span> <span class="special">}</span>
  <span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">typename</span> <span
                class="identifier">CompletionHandler</span><span class="special">&gt;</span>
    <span class="keyword">void</span> <span class="keyword">operator</span><span class="special">()(</span><span
                class="identifier">CompletionHandler</span><span class="special">&amp;&amp;</span> <span
                class="identifier">completion_handler</span><span class="special">)</span> <span
                class="keyword">const</span><span class="special">;</span>
<span class="keyword">private</span><span class="special">:</span>
  <span class="identifier">Executor</span> <span class="identifier">ex_</span><span class="special">;</span> <span
                class="comment">// exposition only</span>
<span class="special">};</span>
</pre>
    <p>
        The function call operator of <code class="computeroutput"><span class="identifier">Init</span><span
            class="special">:</span></code>
    </p>
    <div class="itemizedlist">
        <ul class="itemizedlist" type="disc">
            <li class="listitem">
                <p class="simpara">
                    Obtains the handler's associated executor object <code class="computeroutput"><span
                        class="identifier">ex1</span></code>
                    of type <code class="computeroutput"><span class="identifier">Ex1</span></code> by performing
                </p>
                <pre class="programlisting"><span class="keyword">auto</span> <span class="identifier">ex1</span> <span
                        class="special">=</span> <span class="identifier">get_associated_executor</span><span
                        class="special">(</span><span class="identifier">handler</span><span
                        class="special">,</span> <span class="identifier">ex</span><span class="special">);</span>
</pre>
            </li>
            <li class="listitem">
                <p class="simpara">
                    Obtains the handler's associated allocator object <code class="computeroutput"><span
                        class="identifier">alloc</span></code>
                    by performing
                </p>
                <pre class="programlisting"><span class="keyword">auto</span> <span
                        class="identifier">alloc</span> <span class="special">=</span> <span class="identifier">get_associated_allocator</span><span
                        class="special">(</span><span class="identifier">handler</span><span class="special">);</span>
</pre>
            </li>
            <li class="listitem">
                <p class="simpara">
                    If <code class="computeroutput"><span class="identifier">execution</span><span
                        class="special">::</span><span class="identifier">is_executor</span><span
                        class="special">&lt;</span><span class="identifier">Ex1</span><span
                        class="special">&gt;::</span><span class="identifier">value</span></code> is true, constructs a
                    function
                    object <code class="computeroutput"><span class="identifier">f</span></code> with a member
                    <code class="computeroutput"><span class="identifier">executor_</span></code> that is initialised
                    with <code class="computeroutput"><span class="identifier">prefer</span><span
                        class="special">(</span><span class="identifier">ex1</span><span class="special">,</span> <span
                        class="identifier">execution</span><span class="special">::</span><span class="identifier">outstanding_work</span><span
                        class="special">.</span><span class="identifier">tracked</span><span
                        class="special">)</span></code>,
                    a member <code class="computeroutput"><span class="identifier">handler_</span></code> that
                    is a decay-copy of <code class="computeroutput"><span
                        class="identifier">completion_handler</span></code>,
                    and a function call operator that performs:
                </p>
                <pre class="programlisting"><span class="keyword">auto</span> <span class="identifier">a</span> <span
                        class="special">=</span> <span class="identifier">get_associated_allocator</span><span
                        class="special">(</span><span class="identifier">handler_</span><span class="special">);</span>
<span class="identifier">execution</span><span class="special">::</span><span class="identifier">execute</span><span
                            class="special">(</span>
    <span class="identifier">prefer</span><span class="special">(</span><span class="identifier">executor_</span><span
                            class="special">,</span>
      <span class="identifier">execution</span><span class="special">::</span><span
                            class="identifier">blocking</span><span class="special">.</span><span class="identifier">possibly</span><span
                            class="special">,</span>
      <span class="identifier">execution</span><span class="special">::</span><span
                            class="identifier">allocator</span><span class="special">(</span><span
                            class="identifier">a</span><span class="special">)),</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">move</span><span
                            class="special">(</span><span class="identifier">handler_</span><span
                            class="special">));</span>
</pre>
            </li>
            <li class="listitem">
                <p class="simpara">
                    If <code class="computeroutput"><span class="identifier">execution</span><span
                        class="special">::</span><span class="identifier">is_executor</span><span
                        class="special">&lt;</span><span class="identifier">Ex1</span><span
                        class="special">&gt;::</span><span class="identifier">value</span></code> is false, constructs a
                    function
                    object <code class="computeroutput"><span class="identifier">f</span></code> with a member
                    <code class="computeroutput"><span class="identifier">work_</span></code> that is initialised
                    with <code class="computeroutput"><span class="identifier">make_work_guard</span><span
                        class="special">(</span><span class="identifier">ex1</span><span class="special">)</span></code>,
                    a member <code class="computeroutput"><span class="identifier">handler_</span></code>
                    that is a decay-copy of <code class="computeroutput"><span
                        class="identifier">completion_handler</span></code>,
                    and a function call operator that performs:
                </p>
                <pre class="programlisting"><span class="keyword">auto</span> <span class="identifier">a</span> <span
                        class="special">=</span> <span class="identifier">get_associated_allocator</span><span
                        class="special">(</span><span class="identifier">handler_</span><span class="special">);</span>
<span class="identifier">work_</span><span class="special">.</span><span class="identifier">get_executor</span><span
                            class="special">().</span><span class="identifier">dispatch</span><span
                            class="special">(</span><span class="identifier">std</span><span
                            class="special">::</span><span class="identifier">move</span><span
                            class="special">(</span><span class="identifier">handler_</span><span
                            class="special">),</span> <span class="identifier">a</span><span class="special">);</span>
<span class="identifier">work_</span><span class="special">.</span><span class="identifier">reset</span><span
                            class="special">();</span>
</pre>
            </li>
            <li class="listitem">
                <p class="simpara">
                    If <code class="computeroutput"><span class="identifier">execution</span><span
                        class="special">::</span><span class="identifier">is_executor</span><span
                        class="special">&lt;</span><span class="identifier">Ex</span><span class="special">&gt;::</span><span
                        class="identifier">value</span></code> is true, performs
                </p>
                <pre class="programlisting"><span class="identifier">execution</span><span
                        class="special">::</span><span class="identifier">execute</span><span class="special">(</span>
    <span class="identifier">prefer</span><span class="special">(</span><span class="identifier">ex</span><span
                            class="special">,</span>
      <span class="identifier">execution</span><span class="special">::</span><span
                            class="identifier">blocking</span><span class="special">.</span><span class="identifier">possibly</span><span
                            class="special">,</span>
      <span class="identifier">execution</span><span class="special">::</span><span
                            class="identifier">allocator</span><span class="special">(</span><span class="identifier">alloc</span><span
                            class="special">)),</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">move</span><span
                            class="special">(</span><span class="identifier">f</span><span class="special">));</span>
</pre>
            </li>
            <li class="listitem">
                <p class="simpara">
                    If <code class="computeroutput"><span class="identifier">execution</span><span
                        class="special">::</span><span class="identifier">is_executor</span><span
                        class="special">&lt;</span><span class="identifier">Ex</span><span class="special">&gt;::</span><span
                        class="identifier">value</span></code> is false, performs
                </p>
                <pre class="programlisting"><span class="identifier">ex</span><span class="special">.</span><span
                        class="identifier">dispatch</span><span class="special">(</span><span
                        class="identifier">std</span><span class="special">::</span><span class="identifier">move</span><span
                        class="special">(</span><span class="identifier">f</span><span class="special">),</span> <span
                        class="identifier">alloc</span><span class="special">);</span>
</pre>
            </li>
        </ul>
    </div>
    <h6>
        <a name="asio.reference.dispatch.overload2.h2"></a>
        <span><a name="asio.reference.dispatch.overload2.completion_signature"></a></span><a class="link"
                                                                                             href="overload2.html#asio.reference.dispatch.overload2.completion_signature">Completion
        Signature</a>
    </h6>
    <pre class="programlisting"><span class="keyword">void</span><span class="special">()</span>
</pre>
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                Distributed under the Boost Software License, Version 1.0. (See accompanying
                file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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